Attention deficit disorder, often abbreviated ADD, is a behavior problem in which people have unusual difficulty paying attention, sitting still, or controlling their impulses. The formal term for attention deficit disorder is attention-deficit/hyperactivity disorder (ADHD). ADHD is the most common behavior problem in children. The disorder is diagnosed in boys more than twice as often as in girls. A significant number of teen-agers and adults also have ADHD.
Most experts recognize three types of ADHD. The hyperactive-impulsive type is also called hyperactivity. Children with this type of ADHD are excessively fidgety and restless. They often cannot wait their turn to speak in class or to take part in a group activity. People with the inattentive type of ADHD are not physically restless, but they have trouble concentrating. They are forgetful and disorganized and often fail to finish schoolwork or other tasks. The inattentive type of ADHD occurs more often in girls than does the hyperactive type. Most patients with ADHD have the combined type, which includes symptoms of both the hyperactive and inattentive types.
Most experts think ADHD has a physical cause that has not yet been identified. Scientists now study brain function using magnetic resonance imaging and other techniques that harmlessly produce images of the living brain. Such studies show that the brains of children with ADHD differ from those of children without the condition. Some of these differences occur in regions of the brain called the frontal lobes that control planning and setting limits on behavior. Other studies suggest that certain genes (the hereditary material in cells) play a role in many cases of ADHD.
Most physicians believe that certain medications help people with ADHD. The drug most often prescribed is methylphenidate, known by the trade name Ritalin. Ritalin and similar drugs appear to improve self-control by stimulating the parts of the brain that regulate brain activity. Children with ADHD also benefit from behavior modification. In this therapy, adults help children gain self-control by providing close supervision as well as frequent rewards for appropriate behavior.
